Less than 1% of radiologic studies revealed metastases in patients who had carcinoma in situ, T1N0 cancer, or T1N1 cancer. Yet, those three diagnoses accounted for almost 60% of the radiologic staging tests ordered between 1990 and 1994 at the Hoag Cancer Center, said Robert Dillman, MD, director of the Center.

"This isnt just routine screening of patients with symptoms or abnormal lab tests," Dr. Dillman said at a poster session of the San Antonio Breast Cancer Symposium. "These were early-stage newly diagnosed patients who may or may not have had symptoms or abnormal lab tests. If anything, the findings overestimate the value of testing. There is just no value in radiologic tests for asymptomatic patients who have small tumors."

From the Hoag tumor registry, Dr. Dillman extracted data on all breast cancer patients who were diagnosed or initially treated at the center between 1990 and 1994. Of the 1,203 patients identified, 18% had carcinoma in situ, 54% had localized cancer, 24% had regional spread, and 3% had distant metastases.

A total of 1,965 radiologic staging tests were requested for the patients. The most frequently ordered tests were bone scans (653), chest x-rays (649), abdominal ultrasound (243), and abdominal CT scans (151).

Among all patients with early-stage breast cancer (in situ, T1N0, T1N1), four of 1,128 radiologic tests had positive findings (0.35%). All four involved patients who had T1N0 cancers, and the positive tests were among 735 ordered for patients with that type of cancer (see table).

For patients with T2N0 and T2N1 disease, 18 of 466 radiologic tests (3.8%) were positive. The proportion of positive tests rose to 15% for patients who had T1N2, T2N2, T3, or T4 cancer. The results show "there is no need to perform radiologic staging tests in early-stage patients in the absence of suspicious laboratory tests or symptoms."

Dr. Dillmans interest in the use of unnecessary radiologic studies dates back to the late 1970s, when he became aware of several studies whose authors arrived at conclusions similar to his own. Additionally, the National Comprehensive Cancer Network (NCCN) has established guidelines that discourage use of radiologic staging tests in patients who have early-stage cancer.

"The idea that radiologic staging tests are a waste of time and money in low- stage breast cancer is not new," he said. "I think these findings validate the NCCN recommendations."

Dr. Dillman shared preliminary findings from the review with the Hoag medical staff in 1995. In another year or so, he hopes to assess the impact, if any, the results have had on the staffs use of radiologic staging tests in breast cancer patients.